1. Field of the Invention
The present invention relates to an operation lamp, especially to an operation lamp having functions of rapidly reflecting and focusing a plurality of LED light source sets. The present invention further provides an illumination unit for operation lamp.
2. Description of Related Art
For performing surgeries, an operation lamp is a must-have device for providing illumination. Conventional operation lamp structures can be categorized to a single-light-source single-reflection-mirror structure and a multi-light source structure. The single-light-source single-reflection-mirror structure adopts a high power, e.g. 150 W, light source, for example a halogen lamp or a high intensity discharge (HID) lamp being served as the required light source and reflected and concentrated by a reflection mirror so as to achieve the purpose of operation. The multi-light source structure adopts plural light sources with 30 to 50 watt, for example halogen lamps or high intensity discharge lamps generate plural light beams, and the light beams are concentrated on a projection surface through a structural adjustment, so as to achieve the purpose of operation. In the multi-light source structure, plural light sources may be installed in one lamp member or individually formed as a small lamp member, then the plural small lamp members are gathered to form a large lamp member.
With the development of high brightness LED, light emitted diodes have been used in operation lamps by some manufacturers, but the individual power of LED is merely 1.5 W to 3 W, which is much less than the power that the mentioned halogen lamp or high intensity discharge lamp can provide. As a result, LED can only be used in a multi-light source structure for providing the sufficient and required illuminant, so the LED operation lamp structure is more complicated than the mentioned single-light-source single-reflection-mirror structure and the multi-light source structure.
In fact, the light temperature of LED is very low and very suitable for the needs of operation lamp, meanwhile the LED color rendering property and color temperature is well developed and it will be the mainstream of next-generation operation lamp. However, an operation lamp has to perform focus or focusing adjustment (adjusting illumination area) within a certain distance and whenever needed, the fixed type light beam generated by a LED street lamp or a conventional lamp can not be adopted; moreover, a LED operation lamp requires multi-directional light emitting diodes to concentrate together, so a concentrated type LED large light source, e.g. a street lam, is not suitable, the reasons are the large light source is not capable of concentrating lights to form a desired light beam, so in actual use, the LED operation lamp needs plural LED small light sources which will complicate the whole structure.
Moreover, light temperature generated by LED is very low, but the heat generated by LED has to be efficiently dissipated, otherwise if the stored heat exceeds the rated LED working temperature, the LED will rapidly decay and lower the luminous flux or even burn itself, the service life thereof is therefore effected. As a result, how to effectively dissipate heat generated by larger amount of light emitting diodes is the must-solved issue for designing a LED operation lamp.
What's more, the light projected by LED is a light with high directivity. For being used in an operation lamp and providing effective light beams, two means are mostly adopted: means of concentrating light via lens or means of reflecting and concentrating light via reflection mirror, wherein means of concentrating light via lens is more direct and the structure thereof is relatively simple. But the means of concentrating light via lens is to directly project high intensity pointy light, thus medical personnel are not suggested to directly look at the lamp member with bare eyes; the means of reflecting and concentrating light via reflection mirror enables the direct light of LED to be projected on a reflection mirror, and the special design of reflection surface, e.g. little grid surface, allows the reflected light to be unified for forming as one light beam, so when a medical personnel looks directly, it is a light on a reflection surface, instead of a high intensity pointy light. As mentioned above, the means of reflecting and concentrating light via reflection mirror is better than the means of concentrating light via lens. However, issues such as how to install a large amount of reflection mirror racks, adjusting and controlling, and heat dissipation are still needed to be improved.